I think photograph from ruanmei.com make these pictures at CES 2012. Not seen on any other site before.
The only difference between the *BUILD* Series 7 and the S7 available today is the included/default operating system. The other difference between the S7 and all the other devices that were shown running Windows 8 pre-beta is that the S7 is, in fact, shipping today - albeit with Windows 7 While there is doubtless *more* interest in the S7 due to Windows 8 - the S7 has been selling despite a LACK of Windows 8 (pre-WDP, that is). That actually tells me that the device itself - not necessarily the OS - or even the operating systems's UI (in the case of the shipping S7 of today, Windows 7) has a lot to do with it. Quite honestly, if I could buy any tablet or slate out there - price not being a barrier - the S7 would, in fact, be on top of the stack.
This is not Correct. the Build Slate has all sort of new hardware modules in it which are missing from the W7 Slate (things you have in nearly every smartphone now) including NFC